I've got a USB (CAD U37) microphone and Audacity. I've been playing around with voice recordings, but whenever I've tried to record the whistle, it clips badly in the second octave, unless I've moved far away, and then the low end is way too soft.

Are there any easy fixes for this? Right now, I've got the microphone in a relatively small, padded closet space for an audio narration project I've got going on. I can get about 24" away from the microphone. I've heard about compressors, and I know someone made a plugin for Audacity, but I don't know if this is only for audio that hasn't already clipped or if it's something that actively manages it. It may be that I need a hardware solution, but I see people on YouTube recording all the time, without bad clipping like I'm seeing. Even my phone seems to do a better job.

Incidentally, I thought this might come in handy for reading passages where there's loud talking or yelling, which of course would be interspersed with far quieter narration.

The question is are you clipping at the ad converter on your sound interface. If that is the case you need to tone the signal down before it gets to that, which is either lowering the gain or an outboard stand alone compressor. In the case of a usb mic there is not real way to get a stand-alone in there as the ad converter is literally inside the mic.